FAQ

General Questions (or where to put them?)

• OpenCPN runs with many OS including Android, Linux (many flavors), Windows & MacOS.
• OpenCPN will never work directly with iphone because the iphone store limits production of a version of OpenCPN.
• OpenCPN can use the Javascript Plugin and Shadow OpenCPN with devices running iNavX
• OpenCPN can be used on an iphone with VNC, see Ipad VNC.
  • Use a small Linux computer like Raspberry Pi 3 running Openplotter.
  • Then use a VNC viewer in full screen mode on an iPhone or iPad to view the RPi screen over Wi-Fi.
  • Put OpenCPN on the RPi and you effectively have OpenCPN on an iThing.
  • You can get the RPi for <$50 US.
  • Screenshot of VNC with an iPad or iPhone
  • 

- There are two versions in the Google Play Store. We suggest you will be happiest with the paid version created by D. Register because it is updated regularly and is current. There is a forum at http://bigdumboat.com/aocpn/forum/ .

Messages like: * “ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.side ALSA lib audio/pcm_bluetooth.c:1614:(audioservice_expect) BT_GET_CAPABILITIES failed : Input/output error(5)” or * “(opencpn:8979): Gdk-CRITICAL : IA_gdk_drawable_get_size: assertion `GDK_IS_DRAWABLE (drawable)' failed” * '(opencpn:8979): Gdk-CRITICAL : IA_gdk_drawable_get_depth: assertion `GDK_IS_DRAWABLE (drawable)' failed Error opening coefficient file“ * ”(opencpn:8979): Gdk-CRITICAL : IA_gdk_window_get_origin: assertion `GDK_IS_WINDOW (window)' failed“ are quite normal and have nothing to do with OpenCPN. Just ignore them!

1. There is a Route Plugin for Great Circles.
2. Raster charts display bearings and headings as straight, measurable lines on the chart. Similarly, Vector ENC's are rendered as Mercator projections in OpenCPN and most other ECS's for the same reason.
3. For typical coastal navigation, errors which occur using rhumb line instead of great circle calculations are small for the distances usually covered by one chart.
4. Mercator Charts and Mercator navigation is the standard for most navigational purposes. Other terms used instead of “Mercator Sailing” is “Loxodrome Sailing” or “Rhumb Line Sailing”.

• Great Circle Routes are explained Great Circle Sailing.
• There is also a plugin available as well as some Supplementary Software to handle great Circles.